Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
SW-09-05
January 22, 2009
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) informs you,
a registered owner or operator, of an aircraft with certain Weber
Aircraft, LLC Model 5150 or 5500 seats installed of the potential that
leg saddles may crack. These seats are approved to Technical Standard
Order (TSO) C39b and/or TSO-C127/C127a and are generally installed on
large, transport category airplanes. The FAA has received reports of
the leg saddles cracking. Additionally, this SAIB applies only to seats
with leg saddle part numbers 847367-723 or 847367-725.
Background
The leg saddles connect the seat legs to the front and rear base
frame tubes. Due to a combination of design and production issues, the
fit between the part number 847367-723 and 847367-725 saddle and the
leg was too tight. This resulted in excessive pre-stresses in the weld
area of the saddle. The repetitive loading of in-service use then
caused these welds to crack. Seats with this condition were
manufactured between July 1, 2000 and September 1, 2002.
In March 2007, Weber issued Service Information Letter, SIL 2806 to
address this issue for the Model 5500 seats. Since that time, they have
received additional information regarding the scope of this problem.
They have released SIL 2933, Revision A, to cover the addition of the
Model 5150 seats. Both SILs alert customers of the potential for
cracking and recommend an inspection and replacement if necessary.
Recommendations
The FAA recommends that you inspect leg saddles with part numbers
847367-723 or 847367-725, manufactured between July 1, 2000 and
September 1, 2002, in accordance with Weber Aircraft Service
Information Letter, SIL 2933, Revision 1, dated December 18, 2008. We
also recommend that you repeat the inspection at 12 month intervals and
replace any cracked saddles. Failure to detect and replace cracked
saddles could result in a reduction of the seat performance and
occupant injury.
For Further Information Contact
Rob Romero, Aerospace Engineer, 2601 Meacham Blvd, Fort Worth, TX
76137; phone: (817) 222-5102; fax: (817) 222-5960; e-mail:
Robert.A.Romero@faa.gov.